MEDIA RELEASE 21 August 2008
Westox Cocoon used to halt deterioration of Australia's oldest European style house
A product that removes salt from masonry has helped stop the deterioration of
Australia's oldest surviving European building Elizabeth Farm, which was built
in 1793 from hand made bricks and Sydney sandstone. Westox's innovative Cocoon
product was used to address deterioration caused by high salt contamination from
Located in the western Sydney suburb of Rosehill, Elizabeth Farm, along with
many other heritage buildings, previously relied on slow working sacrificial
renders to reduce deterioration caused from active and destructive salts in
Property Curator, Gary Crockett from the Historic Houses Trust, said that using
only sacrificial render was time consuming, costly and unreliable so they were
delighted to find a more effective alternative.
"Cocoon appealed to us because of its efficiency. The sacrificial renders we
previously used required ongoing maintenance and never reached a point where the
render could be removed without deterioration reoccurring soon afterwards, but
Cocoon was fast acting and didn't introduce anything foreign or unknown into the
stone work. Plus it is a simple and straightforward procedure," said Crockett.
Rising damp and subsequent salt contamination is a significant cause of
deterioration in heritage buildings. Rising damp refers to a process where
moisture-carrying salt is drawn into the walls of a building. Salt remains after
the moisture evaporates. As more moisture is drawn into the walls the salt
saturation increases, forcing moisture to travel higher up the walls until
equilibrium is reached and gravity overtakes capillary. The pressure caused by
the hydrating and crystallising of the salts inside the surface of the wall
forces paint to blister and plaster, brick or stone surfaces to exfoliate.
Sacrificial renders work by altering the point of evaporation where the
expansion of the salt takes place, so that the render is attacked rather than
the original substrate. Sacrificial renders can be problematic as they can stain
the original surfaces with lime. Where salt levels are high, frequent
reapplication is usually required.
Cocoon is the brainchild of Westox Managing Director Barrie Cooper who spent the
early part of his career as a plasterer. Cooper recognised the need for a
product to remove salt from masonry and developed the product initially to treat
salt contamination at Fort Denison on Sydney Harbour.
Cocoon works by drawing the salt out of the masonry it is applied to. Cocoon is
trowelled on in a 10mm thick layer where it slowly releases water into the
masonry to place the build up of salts in the surface of the wall into solution.
As the cocoon dries, the water containing the salts is drawn into it. The cocoon
is then removed, along with the salt.
"Since applying Cocoon in 2002, we have not had to reapply the product, nor have
we had to re-apply any sacrificial renders and it will be a while before we will
need to reapply Cocoon. The deterioration of the stonework, especially on our
flagstone verandahs, has been stopped," said Crockett.
Westox is Australia's leading supplier of heritage restoration products and
works closely with heritage architects and consultants to preserve buildings in
Australia and around the world.
Westox manufactures over 70 innovative products including surface coatings,
aesthetic protection products and renovation products. The underlying philosophy
behind the product range is that heritage buildings and structures should be
restored in an authentic way to ensure they are preserved for future
Westox can be contacted on 02 9774 4100, 1300westox or www.westox.com.
Released for Westox by Dennis Rutzou Public Relations (www.drpr.com.au)
For further information please call Joanna Gitsham or Nicola Rutzou on (02) 9413